Thread-controlling mechanism



DE FOREST HAWLEY. THREAD CONTROLLING MECHANISM.

APPLICATION FILED SEPT. 28. 1917.

Patented J Illy 27, 1920.

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DE FOREST HAWLEY. THREAD CONTROLLING MEGHANISM.

APPLICATION FILED SEIT. 28. I9I7.

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DE FOREST HAWLEY. THREAD CONTROLLING MECHANISM.

APPLICATION FILED SEPT, 28. 1917. 1,347,810.

Sunnah,

spective needles.

l UNITED STATES PATENT OFFICE.

DE FOREST HAWLEY, OF JOHNSON CITY, NEW YORK, ASSIGNOR TO UNION SPECIAL MACHINE COMPANY, OFCHICAGO, ILLINOIS, A CORPORATION 0F ILLINOIS.

THREAD-CONTROLLING MECHANISM.

Specification of Letters Patent.

Patented July 27, 1920.

Application led September 28, 1917. Serialk No. 193,731.

vof reference marked thereon.

This invention relates to new and useful improvements in mechanisms for controlling the needle threads of two line sewing machines.

Heretofore, it has been customary, in two line sewing machines to control'both needle threads by a single machanism, and by reason of any-inaccuracies in the loopers or in the timing of either looper. to its respective needle, this single controller would fail to separately control Athe respective threads in a manner to form alike the stitches of both lines of stitching. I

It is therefore the principal object of this invention to provide separate and relatively adjustable controlling means for the needle threads whereby either thread may be readily controlled to meet the demands of the corresponding looper, and thereby insure the formation of like stitches inl both lines of stitching.

The invention therefore consists in the matters hereafter described and referred to in the appended claims.

In the accompanying drawings,-

Figure 1 is a front elevation of a two line sewing machine equipped with my improved needle thread controlling mechanism;

Fig. 2 is a partial end elevation thereof, partsbeing shown in section;

Fig. 3 is an enlarged detail View, the needle barbeing at the lower end of its stroke; and

Fig. 4 is a detail perspective view of the thread controlling lever.

My invention is especially adapted for use in a two line machineincluding two needles and two loopers. A needle lever reciprocates the needle bar and the loopers. The needle Athreads Vare led through suitable tensions, through spaced thread guides carried by the needle lever, and thence through thread guides on the needle bar to the re- A thread controlling lever is pivoted on lthe overhanging arm of the machine, and this lever is oscillated at each rise and fall of the presser foot. The end of this controlling lever carries two thread eyelets which are mounted for relative vertical adjustment and are disposed intermediate the two thread guides carried by said needle lever. T he relation of these eyelets relative to the thread guides on the needle lever is what determines the distances the thread loops are run upwardly along the needles during the last part of the downward movement thereof, and consequently this deterf mines the amount 'of thread employed in the formation of each stitch of both lines of stitching. Should one looper cast its needle thread loops before the other casts its loop, or, ifthe cross-sectional thickness of one looper is greater than that of the other looper, then, with only a single controlling means for both threads, the stitches of one line will be looser than the stitches of the other line. By employing separate controllers which are capable of relative adjustments, said objectionable features can be readily eliminated.

Referring to constructionshown in the drawings, the sewing machine includes a bed 1 carrying an overhanging arm 2 in which reciprocates a needle bar 3.- The n eedlebar Bis reciprocated by ya needle lever 4 which is pivoted to said overhanging arm 2 and actuated by a pitman coperating with an eccentric. on the main shaft 6. The needle bar carries two needles 7 and 8, and coperating with these needles are two thread carrying loopers 9 and 10 for forming two lines of double locked stitches. In this instance, both loopers are mounted on a single looper v rocker 11 and this rocker is oscillated by a rod 12 from the needle lever extension 13. Cooperating with the stitch forming mechanism is a four motion feed dog 14 of usual construction and operated in the'ordinary manner in slots formed in the work support. A presser foot 16 coperates with the feed dog and work support, and this foot is carried by a presser bar 17 mounted in suitable bearings in the overhanging arm and normally presseddownwardly by a spring 18 see Fig. 2. i

Needle threads 19-20 are led fromV the supply through tensions 21-22 fixed on the overhanging arm, thence through spaced thread guides 23-24i fixed on the needle y lever, and thence through a suitable guide 25 Y 29 adjustably fixed to the presser bar.

,Y the main controlling lever 27 is an auxiliary controlling lever 3l, thev pivot screw being indicated at 32. p One end of this auxiliary lever carries a fixed thread eyelet 33 which is disposed in substantially the vertical plane extending between the guides 23---2LlVV and including the eyelet 30. The other end of this auxiliary lever is formed with a slot 34C, and a screw 35 passes through said slot and is threaded into the mainycontrolling lever 27. The slot and screw connection permits the auxiliary lever to be adjusted about its pivot so as to vary the vertical position of the eyelet 33 through which the thread 20V is led.

In operation, while the needles are `reach-V ing the lowermost positioii,tlie loopers are retracting and shed their needle-thread loops which were therearound. shed justv as the points of the loopers pass their respective needles, and before the needles reach their lowermost position. Controlling means must therefore' be provided to run said needle-thread loops upwardly along the needles to a point oi suificient height to prevent the loopers from entering said loops for the second time. By reason of the thread guides 23-2lv moving downwardly away ironithe eyelets 30-33, both thread loops `are caused to elevate above the plane oftravel of the loopers. It the points of both loopers do not permit of their respective loops being cast off simultaneously, then one loop will not be pulled upwardly as high as the other, and consequently the larger loop will create looser stitches than the other.

By means of the rack 29 and lever 257, both controlling levers will be automatically and simultaneously adjusted when fabrics of dii ferent thicknesses are being sewed.

Having thus described my invention, what The loops are Furthermore, one needle thread loop may be larger than the other on ac-' are led from the supply to the needles, and

separate means acting on the respective threads between the tension means and the needles for controlling the amount of threadv used inl the formation of each stitch, said separate means including devices whereby` the same may be adjustable to independently vary the degree of control on'the respective threads.V Y o 2. lnV a sewing; machine the combination with an overhanging arm, a needle bar carriedfthereby, needles mountedl on said' bar, a needle lever for reciprocating said needle bar, loopers respectively cooperating withV said need-les, spacedthread guides carried` by said needle lever, and thread eyelets for controlling the* respective threads supported onthe overhanging arm for relative verti cal adjustment and disposedv intermediate said thread guides. Y n Y 3. ln a sewing macliineqthe Ycombination with an overhanging arm, a needle bar car# ri'ed thereby, a needlelever for reciprocating said needle bar, loopers respectively co-y operating with said needles, spaced thread guides carried by said needlelever, a main lever iXedVto4 the overhanging arm and carrying a threadeyelet, andan auxiliary lever Y carried by said main lever andV carrying` athread eyelet, saidfthread eyelets being disposed intermediate said threadl guides, one

of said levers being adjustable relative to the other to-vary the `controlling action of its threadeyelet.

i. A sewing mach-ine' including in combination an overhanging arm, apresser foot, a

presser bar carrying said' presser foot" and Y mounted in the over-hanging arm, a needle bar reciprocating in said overhanging arm, a pair oi' needles carried thereby.a' needle lever for reciprocating said needle bar, a looper Vcooperating with each needle, means mountedon the overhanging arm carrying thread guiding devices, one for each needle thread, thread guiding devices carried by the needle lever and engaging the needle threads at opposite sidesof the first-mentioned guiding devices, devices for connecting said means mounted on the overhanging arm with the presser bar whereby vertical movements of the presser bar shift the guiding devices carried thereby,an d means whereby one of saidV guiding devices may be adjusted rela!- tive 'to the other and'to their connection with the presser bar.

5. A sewing machine including in combi-- nation an overhanging arm, al presser foot, a presser bar supporting said'V presser foot, a plurality of needles; a`v looper` cooperating with each needle, tension devicesV through which the threads are led to the needles, a needle bar carrying said needles, a needle lever operating said bar, spaced thread guides carried by said needle lever, a main thread controlling lever pvoted to the overhangng arm and carrying a thread eyelet for engaging one of the needle threads between the guides 0n the needle lever, an auX- iliary lever adjustably carried by the main lever and carrying a thread eyelet engaging the other needle thread between the thread guides on the needle lever, and means connecting the presser bar With the main lever whereby said main lever is shifted through the vertical movements of the presser bar.

In testimony whereof, I aX my signature, in the presence of two Witnesses.

DE FOREST HAWLEY. Witnesses: I

LOUIS B. KETCHAM, CARL YoUNGs. 

